Kleinere Releases/Beginner Releases

import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.WindowEvent;
import java.awt.event.WindowListener;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JTextField;

@SuppressWarnings("serial")
public class meinFrame extends JFrame {

	JTextField field1,field2;
	JButton button, buttonexit;
	JLabel label1,label2;


public meinFrame() {
	  this.getContentPane().setLayout(null);
	  this.initWindow();
	  this.addWindowListener(new WindowListener() {

		@Override
		public void windowActivated(WindowEvent e) {
			// TODO Auto-generated method stub
			
		}

		@Override
		public void windowClosed(WindowEvent e) {
			// TODO Auto-generated method stub
			
		}

		@Override
		public void windowClosing(WindowEvent e) {
			System.exit(0);
			
		}

		@Override
		public void windowDeactivated(WindowEvent e) {
			// TODO Auto-generated method stub
			
		}

		@Override
		public void windowDeiconified(WindowEvent e) {
			// TODO Auto-generated method stub
			
		}

		@Override
		public void windowIconified(WindowEvent e) {
			// TODO Auto-generated method stub
			
		}

		@Override
		public void windowOpened(WindowEvent e) {
			// TODO Auto-generated method stub
			
		}

		  
	  });
	 

	
	  
  }//end meinFrame
  
  protected void initWindow() {
	  
	  
	  field1 = new JTextField();
	  field2 = new JTextField();
	  button = new JButton("Rechne");
	  buttonexit = new JButton("Ende");
	  label1 = new JLabel("Dezimalzahl :");
	  label2 = new JLabel("Binärzahl :");
	  
	  field1.setBounds(110,10,200,25);
	  field2.setBounds(110,40,200,25);
	  button.setBounds(30,100,100,25);
	  buttonexit.setBounds(150,100,100,25);
	  label1.setBounds(10,10,100,25);
	  label2.setBounds(10,40,100,25);
	  
	  this.getContentPane().add(field1);
	  this.getContentPane().add(field2);
	  this.getContentPane().add(button);
	  this.getContentPane().add(buttonexit);
	  this.getContentPane().add(label1);
	  this.getContentPane().add(label2);
	  this.pack();
	  
	  
	  
	  button.addActionListener(new ActionListener(){

		public void actionPerformed(ActionEvent arg0) {
			Rechne();
		}//end actionperformed
		 
	  });//end actionlistener
	  
	  buttonexit.addActionListener(new ActionListener(){

		public void actionPerformed(ActionEvent e) {
			System.exit(0);
			
		}//end actionperformed
		  
	  });//end actionlistener
	  
  }//end initWindow
  
  public void Rechne() {
	  double dezimal = 0;
	  try {
	    dezimal = Double.parseDouble(field1.getText());
	  } catch (NumberFormatException e) {
		dezimal = -1; 
	  }//end try
	  
	  if (dezimal >=0) {
		  int dez = (int) dezimal;
		  char[] erg = new char[8];
		if(dez<=255){
			if(128<=dez){
				dez = dez - 128;
				erg[0] = '1';
			} else {
				erg[0] = '0';
			}
			if(64<=dez){
				dez = dez - 64;
				erg[1] = '1';
			} else {
				erg[1] = '0';
			}
			if(32<=dez){
				dez = dez - 32;
				erg[2] = '1';
			} else {
				erg[2] = '0';
			}
			if(16<=dez){
				dez = dez - 16;
				erg[3] = '1';
			} else {
				erg[3] = '0';
			}
			if(8<=dez){
				dez = dez - 8;
				erg[4] = '1';
			} else {
				erg[4] = '0';
			}
			if(4<=dez){
				dez = dez - 4;
				erg[5] = '1';
			} else {
				erg[5] = '0';
			}
			if(2<=dez){
				dez = dez - 2;
				erg[6] = '1';
			} else {
				erg[6] = '0';
			}
			if(1<=dez){
				dez = dez - 1;
				erg[7] = '1';
			} else {
				erg[7] = '0';
			}
          
     
          String s = String.valueOf(erg);
          field2.setText(s);
          
		}//end if
		else {
			field2.setText("Zahl ist über 255");
		}//end else
	  }//end if
	  else {
		  field2.setText("Fehler bei der Eingabe");
	  }//end else
	  
  }//end Überprüfe
	
	
}//end class

public class Main {


	public static void main(String[] args) {
		meinFrame gui = new meinFrame();
		gui.setVisible(true);
		gui.setBounds(500,100,350,200);
		gui.setTitle("Dezimal zu Binär");

	}

}